Consider a relational table with a single record for each enrolled student with the following attributes1. Eno: Unique enrollment number for each enrolled student2. UID: Unique identity number at the national level for each citizen3. Acc_no: Unique account number at the bank. A student can have multiple accounts or joint accounts.. This attributes stores the primary account number.4. Name: Name of the student5. Phone: Phone number of the studentWhich of the following options is incorrect?

UID is a candidate key, if all students are from the same country

If S is a superkey such that S ∩ UID is Null then S U UID is also a super key

Consider a relational table with a single record for each enrolled stu

1.	Consider a relational table with a single record for each enrolled student with the following attributes1. Eno: Unique enrollment number for each enrolled student2. UID: Unique identity number at the national level for each citizen3. Acc_no: Unique account number at the bank. A student can have multiple accounts or joint accounts.. This attributes stores the primary account number.4. Name: Name of the student5. Phone: Phone number of the studentWhich of the following options is incorrect?
A.	Acc_no is candidate key
B.	ENo can be a primary key
C.	UID is a candidate key, if all students are from the same country
D.	If S is a superkey such that S ∩ UID is Null then S U UID is also a super key
Answer» B. ENo can be a primary key

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